No, there was no alternate universe. Alex and Katherine’s lives were parallel than anything, just missing each other. He would pass by her and she would look up, rubbing her chest where her heart lay hidden beneath, wondering what was missing from her life. That deep longing would eventually pass and fade until their paths almost crossed again. Eyes missing each other, hands grazing other objects, shoulders bumping into strangers.
No, there was no meet-cute for them. Introductions must be made and if the Universe wasn’t going to cross their paths, perhaps it was time for Fate to step in.